Physcocarpus plant named ‘SMPOTW’

ABSTRACT

A new and distinct cultivar of  Physocarpus  plant named ‘SMPOTW’, characterized by its compact, upright and uniform plant habit; vigorous growth habit; freely branching habit; dense and bushy habit; small dark green-colored leaves that become greyed purple in color under high light (full sun) conditions and red during the autumn; showy inflorescences with numerous pink-colored flower buds and white and pink-colored flowers; good garden performance; and resistance to Powdery Mildew.

Botanical designation: Physocarpus opulifolius.

Cultivar denomination: ‘SMPOTW’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct Physocarpus plant, botanically known as Physocarpus opulifolius and hereinafter referred to by the name ‘SMPOTW’.

The new Physocarpus plant is a product of a controlled breeding program conducted by the Inventor in Grand Haven, Mich. The objective of the breeding program is to create new Physocarpus plants with unique flower forms.

The new Physocarpus plant originated from an open-pollination during the summer of 2006 in Grand Haven, Mich. of Physocarpus opulifolius ‘Seward’, disclosed in U.S. Plant Pat. No. 14,821, as the female, or seed, parent with an unknown selection of Physocarpus opulifolius as the male, or pollen, parent. The new Physocarpus plant was discovered and selected by the Inventor in 2008 as a single flowering plant within the progeny of the stated open-pollination in a controlled environment in Grand Haven, Mich.

Asexual reproduction of the new Physocarpus plant by softwood cuttings in a controlled environment in Grand Haven, Mich. since July, 2008 has shown that the unique features of this new Physocarpus plant are stable and reproduced true to type in successive generations of asexual reproduction.

SUMMARY OF THE INVENTION

Plants of the new Physocarpus have not been observed under all possible environmental conditions and cultural practices. The phenotype may vary somewhat with variations in environmental conditions such as temperature and light intensity without, however, any variance in genotype.

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘SMPOTW’. These characteristics in combination distinguish ‘SMPOTW’ as a new and distinct Physocarpus plant:

-   -   1. Compact, upright and uniform plant habit.     -   2. Vigorous growth habit.     -   3. Freely branching habit; dense and bushy habit.     -   4. Small dark green-colored leaves that become greyed purple in         color under high light (full sun) conditions and red during the         autumn.     -   5. Showy inflorescences with numerous pink-colored flower buds         and white and pink-colored flowers.     -   6. Good garden performance.     -   7. Resistant to Powdery Mildew.

Plants of the new Physocarpus can be compared to plants of the female parent, ‘Seward’. Plants of the new Physocarpus differ from plants of ‘Seward’ in the following characteristics:

-   -   1. Plants of the new Physocarpus are more compact than plants of         ‘Seward’.     -   2. Plants of the new Physocarpus have smaller leaves than plants         of ‘Seward’.     -   3. Plants of the new Physocarpus and ‘Seward’ differ in leaf         color as plants of ‘Seward’ have dark purple-colored leaves.     -   4. Flowers of plants of the new Physocarpus are darker pink in         color than flowers of plants of ‘Seward’.

Plants of the new Physocarpus can be compared to plants of the Physocarpus ‘Little Devil’, not patented. In side-by-side comparisons conducted in Grand Haven, Mich., plants of the new Physocarpus differed from plants of ‘Little Devil’ in the following characteristics:

-   -   1. Plants of the new Physocarpus were more compact than plants         of ‘Little Devil’.     -   2. Plants of the new Physocarpus and ‘Little Devil’ differed in         leaf color.     -   3. Plants of the new Physocarpus were more resistant to Powdery         Mildew than plants of ‘Little Devil’.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying colored photographs illustrate the overall appearance of the new Physocarpus, showing the colors as true as it is reasonably possible to obtain in colored reproductions of this type. Colors in the photographs may differ slightly from the color values cited in the detailed botanical description which accurately describe the colors of the new Physocarpus.

The photograph on the first sheet is a side perspective view of a typical flowering plant of ‘SMPOTW’ grown under full sun conditions in an outdoor nursery in late spring/early summer.

The photograph on the second sheet is a close-up view of a typical plant of ‘SMPOTW’ grown under full sun conditions in an outdoor nursery in the autumn.

DETAILED BOTANICAL DESCRIPTION

The aforementioned photographs and following observations, measurements and values describe plants grown during the late spring, summer and autumn under full sun conditions in ground beds in an outdoor nursery in Grand Haven, Mich. and under cultural practices typical of commercial production. Plants were three years old when the photographs and the description were taken. In the description, color references are made to The Royal Horticultural Society Colour Chart, 1995 Edition, except where general terms of ordinary dictionary significance are used.

-   Botanical classification: Physocarpus opulifolius ‘SMPOTW’. -   Parentage:     -   -   Female, or seed, parent.—Physocarpus opulifolius ‘Seward’,             disclosed in U.S. Plant Pat. No. 14,821.         -   Male, or pollen, parent.—Unknown selection of Physocarpus             opulifolius, not patented. -   Propagation:     -   -   Type.—By softwood cuttings.         -   Time to initiate roots, summer.—About 25 days at 24° C.         -   Time to produce a rooted young plant, summer.—About two             months at 24° C.         -   Root description.—Fine to thick; white and brown in color.         -   Rooting habit.—Freely branching; dense. -   Plant description:     -   -   Plant and growth habit.—Perennial shrub; compact, upright             and uniform plant habit; inverted triangle; vigorous growth             habit.         -   Branching habit.—Freely branching habit with about 56             lateral branches developing per plant; pinching enhances             lateral branch development.         -   Plant height.—About 60 cm.         -   Plant diameter (area of spread).—About 56 cm. -   Lateral branch description:     -   -   Length.—About 42 cm.         -   Diameter.—About 3 mm.         -   Internode length.—About 1.7 cm.         -   Texture.—Smooth, glabrous.         -   Aspect.—Erect to about 20° from vertical.         -   Color.—Close to 46A. -   Leaf description:     -   -   Arrangement.—Alternate, simple.         -   Length.—About 3 cm.         -   Width.—About 2.5 cm.         -   Shape.—Ovate.         -   Apex.—Acute.         -   Base.—Obtuse.         -   Margin.—Lobed, serrulate.         -   Texture, upper and lower surfaces.—Smooth, glabrous.         -   Venation pattern.—Pinnate.         -   Color.—Developing leaves, upper surface: Close to 131A.             Developing leaves, lower surface: Close to 197A. Fully             expanded leaves, upper surface: Close to 131A or 139A;             venation, close to 145B; under full sun conditions, color             becoming closer to 187A; during the autumn, color becoming             closer to 180A to 180B and 45A, 45B, 45C and 45D. Fully             expanded leaves, lower surface: Close to 148B; venation,             close to 145C.         -   Petioles.—Length: About 1 cm. Diameter: About 1 mm. Texture,             upper and lower surfaces: Smooth, glabrous. Color, upper and             lower surfaces: Close to 160A. -   Flower description:     -   -   Flower appearance and arrangement.—Single rotate flowers             arranged in terminal and axillary corymbs; corymbs             hemispherical in shape; freely flowering habit with usually             about 24 flowers per inflorescence and about 264 flowers             developing per lateral branch; flowers face upright to             outwardly.         -   Flower longevity.—Flowers last for about three to four weeks             on the plant; flowers not persistent.         -   Natural flowering season.—Plants flower from May though June             in Michigan.         -   Fragrance.—None detected.         -   Inflorescence height.—About 2 cm.         -   Inflorescence diameter.—About 2 cm.         -   Flower diameter.—About 5 mm.         -   Flower length (height).—About 4 mm.         -   Flower buds.—Length: About 3 mm. Diameter: About 3 mm.             Shape: Rounded. Color: Close to 57D.         -   Petals.—Quantity and arrangement: Five petals in a single             whorl. Length: About 3 mm. Width: About 3 mm. Shape:             Elliptic to obovate. Apex: Obtuse. Margin: Entire. Texture,             upper and lower surfaces: Smooth, glabrous. Color: When             opening, upper surface: Close to 155D with central stripes,             close to 58D. When opening, lower surface: Close to 58D.             Fully opened, upper and lower surfaces: Close to 155D with             central stripes, close to 58D.         -   Sepals.—Quantity and arrangement: Five in a single whorl.             Length: About 3 mm. Width: About 2.5 mm. Shape: Broadly             subulate. Apex: Acute. Margin: Entire. Texture, upper and             lower surfaces: Smooth, glabrous. Color: When opening, upper             and lower surfaces: Close to 144A. Fully opened, upper and             lower surfaces: Close to 144A; depending on temperature and             light levels, color may be tinged or lightly cast with close             to 187A.         -   Peduncles.—Length: About 1.5 cm. Diameter: About 2 mm.             Strength: Moderately strong. Texture: Smooth, glabrous.             Color: Close to 144A; depending on temperature and light             levels, color may be tinged or lightly cast with close to             187A.         -   Pedicels.—Length: About 2 cm. Diameter: About 1 mm.             Strength: Moderately strong. Texture: Smooth, glabrous.             Color: Close to 144A; depending on temperature and light             levels, color may be tinged or lightly cast with close to             187A.         -   Reproductive organs.—Androecium: Quantity per flower:             About 30. Anther length: About 0.5 mm. Anther shape: Oblong.             Anther color: Close to 58A. Amount of pollen: Scarce. Pollen             color: Close to 58A. Gynoecium: Quantity per flower: About             three to four. Pistil length: About 0.5 mm. Style length:             About 0.5 mm. Style color: Close to 145D. Stigma appearance:             Globular. Stigma color: Close to 145D. Ovary color: Close to             145D.         -   Fruits.—Length: About 5 mm to 6 mm. Diameter: About 5 mm to             6 mm. Color: When developing, close to 178A becoming closer             to 147A with maturity and eventually drying to close to             200B.         -   Seeds.—Quantity per follicle: If present, about two. Length:             About 2 mm. Diameter: About 1 mm. Shape: Oblong. Color:             Close to 199A to 199B. -   Garden performance: Plants of the new Physocarpus have been observed     to have good garden performance and to tolerate rain, wind and     temperatures ranging from about −25° C. to about 35° C. -   Pathogen & pest resistance: Plants of the new Physocarpus have been     observed to be resistant to Powdery Mildew. Plants of the new     Physocarpus have not been shown to be resistant to pests and other     pathogens common to Physocarpus plants. 

It is claimed:
 1. A new and distinct Physocarpus plant named ‘SMPOTW’ as illustrated and described. 